comparison PyPlugScanner.cpp @ 24:7d28bed0864e

* Rearrange Python plugin construction.

  Formerly, the PyPluginAdapter has retained a single plugin instance pointer
  for each plugin found, and its createPlugin method has simply returned a new
  PyPlugin object wrapping the same instance pointer.  This has a couple of
  negative consequences:
   - Because construction of the actual Python instance occurred before the
     wrapper was constructed, it was not possible to pass arguments (i.e.
     the sample rate) from the wrapper constructor to the Python plugin
     instance constructor -- they had to be passed later, to initialise,
     disadvantaging those plugins that would like to use the sample rate
     for parameter & step/block size calculations etc
   - Because there was only a single Python plugin instance, it was not
     possible to run more than one instance at once with any isolation

  This rework instead stores the Python class pointer (rather than instance
  pointer) in the PyPluginAdapter, and each PyPlugin wrapper instance creates
  its own Python plugin instance.  What could possibly go wrong?

 	//foreach m_path listFiles then return vector<pyPlugs>
 	//format: FullPathString/FileName.py:ClassName
 	
 	vector<string> pyPlugs;
 	string pluginKey;
-	PyObject *pyClassInstance;
+	PyObject *pyClass;
 	
     for (size_t i = 0; i < m_path.size(); ++i) {
         
         vector<string> files = listFiles(m_path[i],"py");
 

              fi != files.end(); ++fi) {
 				string script = *fi;
 				if (!script.empty()) {					
 					string classname=script.substr(0,script.rfind('.'));
 					pluginKey=joinPath(m_path[i],script)+":"+classname;
-					pyClassInstance = getScriptInstance(m_path[i],classname);
-					if (pyClassInstance == NULL) 
+					pyClass = getScriptClass(m_path[i],classname);
+					if (pyClass == NULL) 
 					cerr << "Warning: Syntax error in VamPy plugin:  " 
-					<< classname << ". Avoiding plugin." << endl;
+					     << classname << ". Avoiding plugin." << endl;
 					else { 
 							pyPlugs.push_back(pluginKey);
-							m_pyInstances.push_back(pyClassInstance);
+							m_pyClasses.push_back(pyClass);
 						}
 					//pyPlugs.push_back(pluginKey);
 				}
 		}		
 	}

 return pyPlugs;	
 
 }
 
 
-//For now return one class instance found in each script
+//For now return one class object found in each script
 vector<PyObject*> 
-PyPlugScanner::getPyInstances()
-{
-return m_pyInstances;	
+PyPlugScanner::getPyClasses()
+{
+return m_pyClasses;	
 
 }
 
 
 //Validate
 //This should not be called more than once!
 PyObject* 
-PyPlugScanner::getScriptInstance(string path, string classname)
+PyPlugScanner::getScriptClass(string path, string classname)
 {
 
 	//Add plugin path to active Python Path 
 	string pyCmd = "import sys\nsys.path.append('" + path + "')\n";
 	PyRun_SimpleString(pyCmd.c_str());				

 	PyObject *pyClass = PyDict_GetItemString(pyDict, classname.c_str());
 
 	//Check if class is present and a callable method is implemented
 	if (pyClass && PyCallable_Check(pyClass)) {
 
-		//Create an instance
-		PyObject *pyInstance = PyObject_CallObject(pyClass, NULL);
-		//cerr << "__(getInstance) PyPlugin Class: " << m_class << " successfully created.__" << endl;
-		return pyInstance; 
+	    return pyClass;
 	}	
 	else {
 		cerr << "ERROR: callable plugin class could not be found in source: " << classname << endl 
 			<< "Hint: plugin source filename and plugin class name must be the same." << endl;
 		PyErr_Print();